title: The use of 51Cr for assessing cytotoxicity in an in vitro bioassay for inhibin.
abstract: A cytotoxicity test based on 51Cr release was investigated to assess the specificity of an in vitro bioassay for inhibin utilizing rat anterior pituitary cells in culture. The bioassay is based on a specific suppression of the pituitary cell content of FSH. A variety of substances both of known and unknown toxicity, were bioassayed for inhibin at serial dilutions and the 51Cr release, and FSH and LH cell content levels determined and morphological appearance of the cells evaluated. Results indicated that the 51Cr release procedure was more sensitive and specific in assessing cytotoxicity than either morphological evaluation or LH cell content procedures. In addition, since the 51Cr release was largely independent of the 51Cr concentration, the cell concentration and the age of the culture (2-6 days), this method could be used to assess the quality of, or differences between individual cultures. In conclusion, the 51Cr release procedure provides an additional index for assessing the specificity of the inhibin bioassay as well as an index of the quality of individual cultures. The simplicity and high precision of this cytotoxicity test make it an attractive adjunct to other in vitro bioassay methods.
mesh_terms: D000818:Animals; D001681:Biological Assay / Q000379:methods*; D002860:Chromium Radioisotopes / Q000378:metabolism*; D005640:Follicle Stimulating Hormone / Q000032:analysis; D007987:Gonadotropin-Releasing Hormone / Q000037:antagonists & inhibitors*; D066298:In Vitro Techniques; D007265:Inhibins; D007986:Luteinizing Hormone / Q000032:analysis; D008297:Male; D010902:Pituitary Gland / Q000187:drug effects / Q000378:metabolism; D011506:Proteins / Q000032:analysis*; D012756:Sheep; D013735:Testicular Hormones / Q000032:analysis*
chemical_list: D002860:Chromium Radioisotopes; D011506:Proteins; D013735:Testicular Hormones; D007987:Gonadotropin-Releasing Hormone; D007265:Inhibins; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone